Various medical procedures require the use of introducers for introducing medical devices and instruments to targeted organs to be treated. Various techniques can be employed to minimize the likelihood of introducing air or other gases into the patient during such procedures. There is a continuing need for improved introducer systems and related instrumentation.
Owing to some interventional procedures that require vascular access, a patient can be catheterized through a vein or artery and a catheter can be routed to the heart or any other cardiovascular region. Many procedures, for example, aortic valve replacement, mitral valve repair, mitral appendage occlusion, etc., may require to be performed via catheters. The initial steps can involve placement of a hollow device within a blood vessel. The hollow device can be a sheath or a catheter. The hollow device is inserted into the body of a patient such that a proximal end of the device is outside the body and a distal of the device is inside the body. The proximal end of the hollow device can then be pushed so as to actuate the distal end of the hollow device farther into the blood vessel. A situation can be formed where a pressure difference can occur between the proximal end and the distal end of the device. If the pressure at the proximal end is greater than the pressure at the distal end, a negative pressure gradient can be formed or a pressure drop can occur. A low pressure can be created at the wake of the hollow device and this pressure difference can cause air to leak into the hollow device. Also, when the hollow device is pushed faster, a vacuum can be created inside the hollow device due to the pressure difference and this vacuum creation can cause air to leak into the hollow device. In such a case, air could escape into the blood stream of the patient in the form of air bubbles resulting in air embolism. An attempt to flush the hollow device, after the air bubbles have reached the distal end of the device, can push the air into the patient. Often, even an experienced operator may not be aware of the air introduction until it is already in a fluoroscopic area. As more complex and bulky devices are delivered, the risk of introduction of air into the patient can increase. Therefore, air needs to be trapped and removed before it reaches the distal end of the device.
Devices available for removing air can involve the use of stopcocks, adjustable valves, and various other devices. Owing to creation of high pressure or vacuum, these devices can be more prone to malfunction or failure as both vacuum and high pressure would increase stress on any of these devices. Malfunction or failure of these devices can lead to air embolism, thereby posing a serious threat to the patient. Hence, there is need for a device that can prevent air embolism with minimal and non-vital dependence on valves, stopcocks, screws, and other similar devices.